diff --git a/src/rail_cmd.cpp b/src/rail_cmd.cpp
--- a/src/rail_cmd.cpp
+++ b/src/rail_cmd.cpp
@@ -303,7 +303,7 @@ static inline bool ValParamTrackOrientat
  * @param p1 railtype of being built piece (normal, mono, maglev)
  * @param p2 rail track to build
  */
-CommandCost CmdBuildSingleRail(TileIndex tile, uint32 flags, uint32 p1, uint32 p2, const char *text)
+CommandCost CmdBuildSingleRail(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
 {
 	Slope tileh;
 	RailType railtype = (RailType)p1;
@@ -442,7 +442,7 @@ CommandCost CmdBuildSingleRail(TileIndex
  * @param p1 unused
  * @param p2 rail orientation
  */
-CommandCost CmdRemoveSingleRail(TileIndex tile, uint32 flags, uint32 p1, uint32 p2, const char *text)
+CommandCost CmdRemoveSingleRail(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
 {
 	Track track = (Track)p2;
 	TrackBits trackbit;
@@ -668,7 +668,7 @@ static CommandCost ValidateAutoDrag(Trac
  * - p2 = (bit 4-6) - track-orientation, valid values: 0-5 (Track enum)
  * - p2 = (bit 7)   - 0 = build, 1 = remove tracks
  */
-static CommandCost CmdRailTrackHelper(TileIndex tile, uint32 flags, uint32 p1, uint32 p2, const char *text)
+static CommandCost CmdRailTrackHelper(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
 {
 	CommandCost ret, total_cost(EXPENSES_CONSTRUCTION);
 	Track track = (Track)GB(p2, 4, 3);
@@ -718,7 +718,7 @@ static CommandCost CmdRailTrackHelper(Ti
  * - p2 = (bit 7)   - 0 = build, 1 = remove tracks
  * @see CmdRailTrackHelper
  */
-CommandCost CmdBuildRailroadTrack(TileIndex tile, uint32 flags, uint32 p1, uint32 p2, const char *text)
+CommandCost CmdBuildRailroadTrack(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
 {
 	return CmdRailTrackHelper(tile, flags, p1, ClrBit(p2, 7), text);
 }
@@ -734,7 +734,7 @@ CommandCost CmdBuildRailroadTrack(TileIn
  * - p2 = (bit 7)   - 0 = build, 1 = remove tracks
  * @see CmdRailTrackHelper
  */
-CommandCost CmdRemoveRailroadTrack(TileIndex tile, uint32 flags, uint32 p1, uint32 p2, const char *text)
+CommandCost CmdRemoveRailroadTrack(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
 {
 	return CmdRailTrackHelper(tile, flags, p1, SetBit(p2, 7), text);
 }
@@ -748,7 +748,7 @@ CommandCost CmdRemoveRailroadTrack(TileI
  * @todo When checking for the tile slope,
  * distingush between "Flat land required" and "land sloped in wrong direction"
  */
-CommandCost CmdBuildTrainDepot(TileIndex tile, uint32 flags, uint32 p1, uint32 p2, const char *text)
+CommandCost CmdBuildTrainDepot(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
 {
 	Slope tileh;
 
@@ -812,7 +812,7 @@ CommandCost CmdBuildTrainDepot(TileIndex
  * @param p2 used for CmdBuildManySignals() to copy direction of first signal
  * TODO: p2 should be replaced by two bits for "along" and "against" the track.
  */
-CommandCost CmdBuildSingleSignal(TileIndex tile, uint32 flags, uint32 p1, uint32 p2, const char *text)
+CommandCost CmdBuildSingleSignal(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
 {
 	Track track = (Track)GB(p1, 0, 3);
 	bool ctrl_pressed = HasBit(p1, 3); // was the CTRL button pressed
@@ -1024,7 +1024,7 @@ static bool CheckSignalAutoFill(TileInde
  * - p2 = (bit  7- 9) - default signal type
  * - p2 = (bit 24-31) - user defined signals_density
  */
-static CommandCost CmdSignalTrackHelper(TileIndex tile, uint32 flags, uint32 p1, uint32 p2, const char *text)
+static CommandCost CmdSignalTrackHelper(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
 {
 	CommandCost ret, total_cost(EXPENSES_CONSTRUCTION);
 	int signal_ctr;
@@ -1150,7 +1150,7 @@ static CommandCost CmdSignalTrackHelper(
  * - p2 = (bit 24-31) - user defined signals_density
  * @see CmdSignalTrackHelper
  */
-CommandCost CmdBuildSignalTrack(TileIndex tile, uint32 flags, uint32 p1, uint32 p2, const char *text)
+CommandCost CmdBuildSignalTrack(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
 {
 	return CmdSignalTrackHelper(tile, flags, p1, p2,text);
 }
@@ -1164,7 +1164,7 @@ CommandCost CmdBuildSignalTrack(TileInde
  *           - (bit  4)    - 0 = signals, 1 = semaphores
  * @param p2 unused
  */
-CommandCost CmdRemoveSingleSignal(TileIndex tile, uint32 flags, uint32 p1, uint32 p2, const char *text)
+CommandCost CmdRemoveSingleSignal(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
 {
 	Track track = (Track)GB(p1, 0, 3);
 
@@ -1219,7 +1219,7 @@ CommandCost CmdRemoveSingleSignal(TileIn
  * - p2 = (bit 24-31) - user defined signals_density
  * @see CmdSignalTrackHelper
  */
-CommandCost CmdRemoveSignalTrack(TileIndex tile, uint32 flags, uint32 p1, uint32 p2, const char *text)
+CommandCost CmdRemoveSignalTrack(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
 {
 	return CmdSignalTrackHelper(tile, flags, p1, SetBit(p2, 5), text); // bit 5 is remove bit
 }
@@ -1244,7 +1244,7 @@ Vehicle *UpdateTrainPowerProc(Vehicle *v
  * @param p1 start tile of drag
  * @param p2 new railtype to convert to
  */
-CommandCost CmdConvertRail(TileIndex tile, uint32 flags, uint32 p1, uint32 p2, const char *text)
+CommandCost CmdConvertRail(TileIndex tile, DoCommandFlag flags, uint32 p1, uint32 p2, const char *text)
 {
 	CommandCost cost(EXPENSES_CONSTRUCTION);
 	RailType totype = (RailType)p2;
@@ -1417,7 +1417,7 @@ CommandCost CmdConvertRail(TileIndex til
 	return (cost.GetCost() == 0) ? CMD_ERROR : cost;
 }
 
-static CommandCost RemoveTrainDepot(TileIndex tile, uint32 flags)
+static CommandCost RemoveTrainDepot(TileIndex tile, DoCommandFlag flags)
 {
 	if (!CheckTileOwnership(tile) && _current_company != OWNER_WATER)
 		return CMD_ERROR;
@@ -1446,7 +1446,7 @@ static CommandCost RemoveTrainDepot(Tile
 	return CommandCost(EXPENSES_CONSTRUCTION, _price.remove_train_depot);
 }
 
-static CommandCost ClearTile_Track(TileIndex tile, byte flags)
+static CommandCost ClearTile_Track(TileIndex tile, DoCommandFlag flags)
 {
 	CommandCost cost(EXPENSES_CONSTRUCTION);
 	CommandCost ret;
@@ -2547,7 +2547,7 @@ static CommandCost TestAutoslopeOnRailTi
 	return  cost;
 }
 
-static CommandCost TerraformTile_Track(TileIndex tile, uint32 flags, uint z_new, Slope tileh_new)
+static CommandCost TerraformTile_Track(TileIndex tile, DoCommandFlag flags, uint z_new, Slope tileh_new)
 {
 	uint z_old;
 	Slope tileh_old = GetTileSlope(tile, &z_old);